Changing from Reef to Fresh Water


Last Gasp
I have made my final decision to change my 10 year old tank (48" x 24" x 18") from a reef aquarium with limited hardy corals and 11 community fish to a fresh water system.:grumble:

I have reluctantly reached this stage as I cannot get rid of a cyano bloom after much money being chucked in the direction of the aquarium. I have increased the water flow, changed new T5 lights, purchased a new RO unit, made regular water changes, tried various products, including 'eXcital' that claims it destroys red slime algae.

I am at the end of my tether and not prepared to throw much more money at a lost cause.

So, fellow reefers, I know this will hurt your feelings, but I seek advice on what I need to do to make an economical change to keeping freshwater discus fish for example.

Of course, I will need to clear the tank and clean it without using chemicals, bleach products etc. I will hand over my much loved healthy community fish to the local aquarium center. This will bring a tear to my eye as I have lived through 10 years with some of the fish, including a beautiful queen angel.

The live rock is comtaminated with cyano, so I am expecting you to advise me to put it in the trash can. Can I boil the live rock and use it in the fresh water tank as decoration?
Can I keep the protein skimmer working in a fresh water system?

Any advice about the whole process will be very much appreciated.:sfish:
Sorry to hear....Care to share with us what you've tried? Maybe there's still hope yet?

In any case, no, the skimmer will not work in freshwater. And I would use regular table salt to scrub the tank, and vinegar to properly clean it. Then just rinse.
Also, can you post a picture of the cyano - we've had a number of people here who thought they had cyano only to have it turn out to be something else
Sorry to hear that you're leaving, but we've all been down this road with algae. Have you tried the hydrogen peroxide trick(soak the rocks in h2o2 and scrub it in the solution)? It kills all types of algaes, and after that do a black out for a few days and then do a nice sized water change. Good luck with everything.
Did you try Chemi-Clean. I battled for months and finally got sick of it and it took 4 days and has been months with nothing.

Make sure to slap new Chaeto in after or even during.
Thanks all for the responses.
I live in England and not sure if the trade name, 'Chemi-Clean is sold here.
I'll see if it or similar is available over the counter.

Sorry to sound ignorant, but I don't know what 'Chaeto' is - let me know and I'll follow your directions.
It is this Saltwater Aquarium Algae for Marine Reef Aquariums: Chaetomorpha Algae - Aquacultured

It is really called Chaetomorpha Algae

I had a lot but when I had the Cyano outbreak it sucked up the nutrient causing the Chaeto to die off.

Basically I was visiting a high end aquarium store not just a typical pet store. This place builds and maintain high end tanks. So I just happened to mention my problem and the guy said look you can try these 2. So he gave me the Chemi-Clean. He said he has used it with success many times and showed me the tanks it was put in.

I really advise against anything unless it is a last resort.

So what I did was this.

1) I measured out the Chemiclean by the recommended drops because the dropper is inconsistent. I actually spoke with the owner through email and he said they were already looking into it. You will get a squirt then a drop and then 3 drops quick. It can be annoying and while my measurement was not exact it was close. Plus I didn't mind a little extra.

I has I think like 200 drops or something high so it was a pain. I then shut off the skimmer. It will just overflo the whole time.

2) I shut the skimmer.

3) I cleaned as much of the Cyano out manually.

4) I put the Chemi-clean in the tank and made sure it spread well. I just didn't dump it in the corner.

5) I put in an air-stone and monitored the PH. If it got to high you take it out for a little while but honestly it never budged over 8.2. I think that the hype around the PH rise is overblown. At least for me it was simple in that area.

6) It said 3 days but I actually added a few(20) extra drop on day 3.

7) Day 4 the tank was spotless. It could take longer but that is ok. Just keep the circulation going.

8) Do a normal(for me) 20% water change. Wait maybe a week and do another. you can turn your skimmer back on but wait till you change the water 2 times to shorten the time it takes to stop overflowing.

9) Turn skimmer on maybe 1 day after you second water change. It will most like start spilling so just have it cleaned and have the drain open to the sump. Mine sits in the sump so I could do that.

I had to do 3 water changes and it took over 2 weeks for my skimmer to calm down. I was not smart enough to leave the skimmer off right away and was listening to someone who used the skimmer to maintain the PH. I doubt that will shorten the overflowing effect because it is about the water and I do not think Chemi-clean would be sticking to the plastic and causing this.

I most likely had a large over-does due to the crappy dropper and of course I added extra to make sure I was feeling good about it.

Just expect to change the water weekly for 2 to 3 weeks and of course I thought the skimmer would never stop but it did.

I also put a large piece of Chaeto in the sump to help lower the Phosphates which I am 99% sure the Cyano loves mmmmmm. Once I saw it was staying green and growing fast I knew it was over.

I since added a 2 Little Fishes Phosphate Reactor and always had Carbon running. Just to make sure it has a really tough time if it tries to make a come back but 3 months later and nothing. maybe longer.

It can be scary to do things like this with all the costly fish and corals but nothing dies in my tank.

The Chemi-clean is formulated differently than other stuff I found and I felt safe with it and can say I had no big issues after using it. Just plan on watching the tank and doing a lot of maintenance right after so have salt ready to mix right away and all that.

Hope this helps you out.
Good luck and sorry for my crappy typing.I read through it and see some wrong words or missed some letters.
People have had mixed experiences with chemi-clean - some people have lost live stock as a result, some have had algae come back in even greater numbers because it develops a resistance to the chemi-clean, and some have had success. Bottom line is that you've ultimately got to identify the source of nutrients feeding the algae in order to begin to eliminate it! Help us out by telling us more about what you feed, how much, and how often? How much flow do you have in your tank? How long do you run your lights for each day? What type of filtration are you using (a sump w/ live rock and a skimmer or something else?) What do you have for a clean up crew? Have you tested for phosphates and nitrates? Hopefully we can help you get it under control before you throw in the towel! Oh, and once again, post a picture of the stuff if you can so that we can confirm it is indeed cyano! :)
Thanks all for the responses.
I live in England and not sure if the trade name, 'Chemi-Clean is sold here.
I'll see if it or similar is available over the counter.

Sorry to sound ignorant, but I don't know what 'Chaeto' is - let me know and I'll follow your directions.

The others have you covered but read this :

  1. I have used chemi-clean and it does work -temporarily. It kills cyano but does not export the nutrients that feed cyano from the system so it comes back.
  2. One thing that a lot of people fail to do and causes cyano is to get good flow going through the refugium that you have filled with cheato. IF the refugium is filled with cheato AND you have strong light on it AND there is strong flow on it (at least 250gph on a 3 gallon fuge) then your cyano will probably go away. If your tank is overstocked well them it might never go away.
  3. Lastly people talk about nitrates BUT phosphates are worse! Test phosphates and think about a phosphate reactor.
I have made my final decision to change my 10 year old tank (48" x 24" x 18") from a reef aquarium with limited hardy corals and 11 community fish to a fresh water system.:grumble:

So, fellow reefers, I know this will hurt your feelings, but I seek advice on what I need to do to make an economical change to keeping freshwater discus fish for example.

Any advice about the whole process will be very much appreciated.:sfish:

Sorry to hear of your problems and frustrations. I keep both fresh and reef tanks. I too wanted to do Discus, but... keeping Discus is one of the most challenging of all aquaria. It is an incredibly high maintenance species. Pristine quality essential, some even do daily, yes daily water changes! There are many other amazing Cichlids I might start with first. Good luck what ever you choose! (ps can't use skimmer in fresh tank)
I bred Discus for years. I would take the maintenance of a reef tank any day over Discus( and yes the discus tank got a 20% H2O change everyday! It was on a drip system that constantly dropped fresh H2O and changed 20% of the water over a 24 hour period) If you are having problems with algae and bacteria forget about Discus. You need to eliminate the extra nutrients in your system that are feeding your problem. If you eliminate the nutrients you will not have these problems. Test for phosphate. Test the water out of your RO unit as well, it might not be functioning properly.
Thanks all for the excellent advice.
Since my last post, I have been working extremely hard to eliminate the red slime algae.
My main tactics have been:
  • 20% water change every 5 days
  • increase the water flow by manually 'swishing' the water over the live rock with my hand. (A bit of a crude technique, but when at tether's end,.....)
  • Of course, this action spreads the red slime algae all through the tank!!!!!
  • The skimmer has been working overtime
  • I have reduced the length of time the lights are on to 4 hours a day (as a remedial action for the last 4 days)
The outcome is that the red slime algae is less obvious (probably because there is not time for it to settle on the rocks, what with the regular water changes and the 'swishing'.-)
I have now noticed an increase in green hair algae.
I have 11 fish in the tank, all healthy and some over 10 years old.
The corals left in the tank are just the hardy - all others have been lost.

Now, I do not have a refugium. I do not have any fitration system except for the ample live rock. The tank system, in years gione by has been very successful with this set up.
I am reluctant to spend loads of cash on mnew gear if there is no promise of it all settling down and returning to that beautiful aquarium that I once had.

Here comes the big question: what can i do to get the tank back to its best?
or - shall I bite the bullet and go fresh water?

Shall I buy a refugium? Will that guarentee success?
I value all your comments and support.
The one thing in this hobby I know is that there is no guarantee. From experience, I've found a refugium to be an asset to my systems because it promotes algae growth in there instead of in the main tank. I didn't have any algae growing in the dt at all. Plus running the fuge lights opposite the main tank kept the PH levels stable.

Can you post your parameters? Check for Phosphates too. I would check your newly made saltwater for phosphates as well as your tank. Detectable phosphates are bad; algae loves that stuff. Usually the kits are useless since it will test 0 because the algae has absorbed it all up.
Parameters for ammonia = 0, Nitrite = 0, Nitrate = 5 ppm, Phosphate = 0.25 ppm

Powerheads = interesting that you mentioned them. I can't read the ratings for the powerheads as they are covered in coraline. However, I have noticed that two have minimal flow. Do you think I need better water circulation? What system would you recommend. I am not too keen on spending loads of money but willing to invest if this will resolve the problem.
I do think flow is a good candidate. If the algae is blowing off into the water column when you agitate the water with your hand then it sounds very much like cyano - and usual culprits (and cures) for cyano are phosphate issues, flow, and lights. You've already replaced your bulbs so that shouldn't be the issue. Your tank is how many gallons? 110 or 120? For comparison purposes, I have a 90g and have two 1400gph, 1 1250gph, 2 750gph (which are on a 3min cycle), and a roughly 500gph return line from my sump - that's a total of roughly 6050gph of flow in my tank. Also, pumps need to be cleaned every few months - even a little bit of algae build up on them can slow them down a lot. I'd recommend cleaning all of your powerheads well, and then adjust them so that at least one of them is pointing directly at one of the rocks that has a cyano bloom. I was dealing with cyano on a particular rock for awhile and once I adjusted a powerhead and increased the amount of flow that spot was getting, the cyano cleared in a few days and hasn't come back. If it clears up in the area that you increase flow in after cleaning your powerheads, then that should give you an idea if flow is at least part of the problem.

Feeding sounds okay, though you might want to cut back to every other day and see if your fish do okay with that. Another potential (though less common) source of phosphates is leaching from the rock. What kind of rock do you have in your tank? A few years back there was a batch of pukani rock that apparently leached a lot of phosphates, and I believe some people have also found phosphates leaching out of some of the man-made rocks. That being said, most phosphate issues are food related, at least from what I've heard.

One other thing I'd recommend is using a turkey baster to blow of the cyano on your rocks just before you do your water change, and then try to suck out as much as possible during the water change.

As far as a clean up crew, you could try getting a few turbo snails - they did a pretty good job eating through the hair algae I had in my tank. But I don't know of anything that touches cyano.

A few final questions - do you have a sump? If so, maybe its time to change out the hoses (they can get all sorts of gunk built up in them over time). What brand of skimmer do you have?